Mechanical pencil



Aug. 20, 1963 c. E. BAIRD MECHANICAL PENCIL Filed Deo. 22, 1961 2Sheets-Sheet 1 c. E. BAIRD MECHANICAL PENCIL Aug. 20, 1963 2Sheets-Sheet 2 Filed Dec. 22, 1961 United States Patent() 3,101,073MECHANICAL PENCIL Charles E. Baird, 500 Coronado Court, Paducah, Ky.Filed Dec. 22, 1961, Ser. No. 161,605 Claims. (Cl. 1Z0- 11) Thisinvention relates to -a novel mechanical pencil.

The primary object yof the invention is the provision of a more eicientand more easily operated mechanical pencil wherein its lead, such asgrease lead, is adapted to be pushed out from a spring-retractedprotected position to a use position, and to be retracted from useposition to retracted position by release of a spring-pressed catchwhich serves also to maintain the lead in use position, the lead beingadapted to be extended, when worn, by screw means. As a result to theseprovisions the time and labor consuming inconveniences of prior greaselead pencils which do not provide for semi-automatic retraction of theirleads from use position, but require manual retraction of the leads, anddo not provide instant push extension of the leads to use position, areeliminated, as well as the tendency of the users of prior pencils toreturn these pencils to the pocket with the leads in extended usepositions and soil the pocket.

Another object of the invention is the provision of a mechanical pencilVof the character indicated above. wherein a rotary push rod serves asthe means for pushing out the lead to use position, and -as the meansfor rotating the screw means for extending or feeding and retraotingspring means serves to retract the lead.

A further object of the invention is the provision of a simple andrugged mechanical pencil of the character indicated above, wherein thecatch is associated with and is partially housed by a pocket clip.

Other important objects `and advantageous features of the invention willbe apparent from the following description yand the accompanyingdrawings, wherein, for purposes of illustration only, a specific form ofthe invention is set forth in detail.

In the drawings:

yFIGURE l isa side elevation of a mechanical pencil of the presentinvention, showing the lead in extended use position in phantom lines;

FIGURE 2 is atop plan view of FIGURE l;

FIGURE 3 is a longitudinal section taken on the line 3-3 of FIGURE 2,showing the lead in retracted position;

FIGURE 4 is a longitudinal section, partially in elevation, taken on theline 4-4 of FIGURE 3;

FIGURE 5 is ya view, similar to FIGURE 3, showing the lead in extendeduse position;

FIGURES 6 and 7 are enlarged transverse sections taken on the lines 6-6and 7--7 of FIGURE 3; and

FIGURE 8 is an enlarged transverse section taken on the l-ine 8-8 ofFIGURE 1.

Referring in detail to the drawings, wherein like numerals designatelike parts throughout the several views, the illustrated mechanicalpencil comprises a tubular cylindrical barrel 10 having a lower end 12and an upper end 14, the barrel being externally rounded at itsupperend, as indicated at 16. The barrel 10 has a uniform diameter main bore18 which extends upwardly from the lower end 12 to a point near to andspaced from the upper end 14, where a reduced diameter axial bore 20extends from the upper end 14 and opens to the main bore 18.

lThe main bore 18 is formed with a pair of longitudinal diametricallyopposed slide grooves 22 which extend downwardly from a location near toand spaced from the reduced bore 20, through -a short internallythreaded portion 24, which extends to the lower end 12 of the barrel 10.-A tubular cylindrical pencil tip or point 26 is provided, which islarger in diameter than Ithe main bore 18 of the barrel 'and has areduced externally threaded portion 28, on its upper end, which threadsinto the threaded pontion 24 of the barrel, and denes a shoulder 30adapted to abut the lower end of the barrel. The tip 26 is provided withan axial bore 32 which extends therethrough and which is larger indiameter than relatively large diameter grease lead 34, which isinitally longer than the tip 26.

1A split tubular spring lead holder 36, which is initially smaller indiameter 4than the lead 34, is adapted to expand on insertion of a leadtherein and then having a close but free sliding t in the tip bore 32.The lead holder 36 is preferably somewhat longer than the tip 26 andhas, on its upper end, `a lateral annular ilange 38, against which yan`annular washer 40 bears. A lead retracting coil spring -42 iscircumposed on the lead holder 36 and is compressed between the washer40 and the upper end 44 of the tip 26.

A relatively short cylindrical pusher block 46 slides in the main barrelbore 18 and has diametrically opposed lateral lugs 48, which slide inthe slide grooves 22 of the bore 1S and prevent rotation of the pusherblock relative to the barrel 10. The spring 42 keeps the lead holderange 38 pressed `against the lower side of the pusher block 46, and theupper side of the pusher block bears `against the lower end 50 of arotatable cylindrical push rod 52.

The pushrod 52 is longer than the distance, at any time, between thepusher block 46 and the upper end 14 of the barrel 10, and comprises lamain portion 54 which rotates freely in the main barrel bore 18 and areduced diameter, knurled upper end portion or knob S6 which rotates inthe reduced bar-rel bore 20, whereby, `at all times, a p0rtion of the1knob 56 extends upwardly from the upper end 14 of the barrel 10. Anexternal annular groove 58 is provided at the upper end of the main pushrod portion 54, in which a metal band 60 is seated and suitably secured,flush with the exterior of the portion 54. The band 60 has an internalannular flange 62, at its upper end, which covers the shoulder 64 at theupper end of the main rod portion 54.

The main push rod portion 54 is provided with an axial blind bore 66which extends to its lower end 50 and has a closed upper end `63 Iat theupper end of the push rod. The blind bore 66 is flat and extendsdiametrically of the rod portion 54 and has dat parallel sides 63 andconcavely lrounded edges 70, so as to conormably and non-rotatablyreceive ya similar cross section lead feeding `and retracting sorew 72having flat parallel sides 74 and oonvexly curved screw-threaded edges76. The screw 72 is preferably slightly longer than the blind bore 66,`and its lower portion is threaded through a threaded bore 73 in thepusher block 46. Clockwise rotation of the push rod 52 by means of theknurled knob 56- produces downward movement of the screw 72, and henceof the lead -34 relative to holder 36, and extends the lead 34 out ofthe holder 36 in order to compensate for wear of the lead 34 entailed inmarking or writing therewith.

The lead 34 is extended from the retracted protective position shown inFIGURE 3 to the extended position shown in FIGURE 5, simply by pressingdownwardly on the push rod knob 56, `and the push nod 52 is heldreleasaibly in this extended position, by means of a springpressed catchlof a pocket clip and catch assembly 78.

The assembly 78 comprises a preferably metal split band 80 whichencircles the barrel 10, adjacent to the upper end 14 thereof, Iand issecured thereto, and has a longitudinal slot 82 therein, whose edges S4bear retainably against the outer surfaces of longitudinal latenallyoutwar ly extending flanges Se, which are seated in gnooves 88, in the:outer surface of the barrel 1l), and which are portions lof theparallel side walls 9h Lof the channelashaped upper portion 92 of adownwardly extending pocket clip 94. The portion 92 has )a web or topwall 95 which extends between the side Walls 9d and which has an upperend portion 96 which curves upwardly and i laterally inward-ly to thebarrel 10, and has an upper edge 98 which is securaoly engaged in a`transverse groove 16MB in the barrel 1t). The gnooves 58 are part of anelongated external recess 1632 in the barrelwhich extends downwardlyfrom the transverse groove 160. Extending downwardly from the upperportion 92 of the pocket clip 94 is a clip arm 164, of limitedilexibility, which is of shallow channel cross section, the sidewallslll and the web 168 of the clip arm 104 being continuations tof theside walls 90 and web 94 of theupper clip portion 92 of the clip.

The lower end of the web 108 or the clip arm 104 terminates Vin alaterally inwardly and upwardly convexed curved hollow tip 110, whichbears against the exterior of the barrel lll.

The assembly 78 further comprises `a catch 112, of relatively thin flatstock, which comprises a longitudinally elongated finger piece 114having intermediate its ends a zdownwardly.extending !fulcrum lug 116which is seated in ia small depression 11S in the bottom 120 of therecess.

The upper part of the catch finger piece 114 works through alongitudinally elongated slot 122 provided in the curved portion 96 ofthe web 95 lof the pocket clip '78, `and extends upwardly beyond the.'clip. The finger piece 114 has a downwardly extending detent 124, onits lower end, which works through a slot 126, formed through the bottomof therecess 162, near the lower end of the recess. The detent 124 has alower edge 123 which, in the engaged position of the catch 112 is, lasshown in FIGURE 5, normal to the axis ott the push rod 52 and inretaining engagement with the upper surface of the ange 62 of the bandtitl, whereby the push rod 52, and hence the lead 34, are maintained inextended position, against the resistance of the spring 42. The innerend of the detent 124 is laterally outwardly and upwardly angled, iasindicated at 130, so that, when the catch 112 is operated to its releaseposition, thedetent 124 can clear the main push rod portion 54, as shownin FIGURE 3, iso as to enable the spring 42 to retract the push rod 52,Iand hence the lead 3d into the pencil tip 26, as shown in FIGURE 3. Theangled end 130 of the detent 124 Vthen rides upon the `outer surface ofthe main push rod portion 54, until and unless the push rod is pusheddownwardly to extend the lead 34 to use position. Y

'Ilhecatch 112 is biased toward its engaged position by means of alongitudinally elongated leaf spring 132, which is outwardly bowed awayfrom the barrel 10. The spring 132 has a return bent terminal 134, onits lower end, which is located retainably within the tip 110 of thepocket clip arm 104, and its main portion 136 bears outwardly againstthe web 108er the pocket clip `arm 164. `The upper end of the spring 132has an out-turned terminal 138 thereon, which bears against a concavelycurved outer edge portion 140 of the linger piece 114, between thefulcrum 116 and the `detent 124, whereby the ldetent 124 is urgedinwardly through the slot 126. 'It will be understood from the foregoingthat extension of Iand locking of the lead 34 to its use position, shownin FIGURE 5, fromthe retracted position shown in FIG- URE 3, requiresonly a downward push on lthe push rod knobV 56, and that retraction ofthe lead to its protected position` within the pencil tip 26, requiresonly inward pressure upon the exposed upper .portion of the catch fingerpiece 114; and that downward rfeeding of the lead 34, relatives to thelead holder 36, requires only rotation of the push rod 52, in the properdirection by means of the knob 56.

Although there has been shown and described herein a preferred lform ofthe invention, it is to be understood that the invention is notnecessarily confined thereto, and

that any change or changes in the structure of andin die relativearrangements of components thereof are contemplated as being within thescope of the invention `as defined lby the claims appended hereto.

What is claimed is:

1. A mechanical pencil comprising a tubular barrel having lower [andupper ends, said barrel having la main axial bore extending to saidlower end and a reduced diameter axial bore extending from said upperend to the main bore, a tubular tip threaded into the lower end of themain bore, said tip having an axial bore smaller in diameter than saidmain bore, a tubular split spring lead holder sliding in the tip boreand having ya lateral annular :Flange on its upper end, a coil springcircumposed on the lead Vholder and compressed between said laterallangeand the tip, la pusher block engaged non-rotatably and slidably inthe main barrel bore and engaged with the upper end of the Ilead holder,ya push rod engaged slidably androtatably in the mainbarrel bore, `afeeding and retracting screw supported within said push rod and threadedthrough said pusher block, said push rod having a reduced diameter knobon its upper end extending through said reduced diameter barrel bore andreaching beyond the upper end of the barrel, the upper end of mainportion ofthe push rod :and said knob defining a shoulder, and laterallyinwardly `spring-pressed catch means ladapted to engage behind saidshoulder in 'a downwardly extended position of the push rodl wherein alead `engaged in the lead holder is extended fout of the tip to useposition.`

2. A mechanical'pencil comprising a tubular barrel having lower andupper ends, said barrel having a main axial bore extending to said lowerend andV a reduced diameter axial bore extending yfrom said upper end tothe main bore, a tubular tip threaded into the lower end of the mainbore,-said tip having an axial bore smaller in diameter than said mainbore, a tubular split spring lead holder sliding in the tip bore andhaving a lateral annular lange 4on its upper end, a coil springcircumposed lon the lead holder and compressed between said lateralflange and Vthe tip, a pusher block engaged non-rotatably and slidablyin the main barrel bore and engaged with the upper end of the leadholder, a push rod engaged slidably and rotatably in the main barrelbore, a feeding and retracting screw supported within said push rod andthreaded through said pusher block, said push rod having a reduced`diameter knob on its upper end extending through said reduced diameterbarrel bore and reaching beyond the upper end of the barrel, the upperend of main portion of the push rod and said knob defining a shoulder,and laterally inwardly spring-pressed catch means adapted to engagebehind said shoulder in a downwardly extended position of the push rodwherein a lead engaged in the lead holder is extended out lof the tip touse position, said catch means being releasable from the shoulder toenable the spring to retract the push rod and retract a lead in the leadholder into the tip.

3. A mechanical pencil comprising `a tubular barrel having lower andupper ends, said barrel having a main axial bore extending to said lowerend and a reduced diameter Vaxial bore extending from said upper end tothe mainhore, a tubular tip threaded in to the lower end ci the mainbore, said tip having an axial bore smaller in diameter than said mainbore, a tubular split spring lead holder sliding in the tip bore .andhaving a lateral annular llange on its upper end, la coil springcircumposed lon the lead holder and compressed between said lateralllange andthe tip, a pusher block engaged non-rotatably and slidably inthe main barrel bore and engaged with the upper end of the lead holder,a push rod engaged slidably androtatably in the main barrel bore, saidpush rod having a reduced diameter knob 'on its upper end extendingthrough said reduced diameter barrel bore and reaching beyond the upperend of the barrel, the upper end of main portion of the push rod andsaid knob delining a shoulder,

and laterally inwardly spring-pressed catch means adapted to engagebehind said shoulder in a downwardly extended position oi the push rodwherein a lead engaged in the lead holder is extended out of the tip touse position, said catch means lbeing releasable from the shoulder toenable the spring to retract the push rod and retract ya lead in thelead holder into the tip, said main push rod portion having an axialblind bore opening to its lower end, said bore being non-cylindrical, alead feeding screw engaged in said blind bore, said screw beingnon-cylindrical `and #being slidably and non-rotatably engaged in lcheblind bore, said pusher block having a threaded axial bore through whichthe screw is threaded, the screw having `a :lower end engageable withthe upper end of a lead engaged in said lead holder.

4. A mechanical pencil comprising a tubular barrel having llower andupper ends, said barrel having a main Vaxial bore extending to saidlower end and a reduced diameter axial bore extending from said upperend to the main bore, a tubular tip threaded into the lower end lof themain bore, said tip having an axial bore smaller in diameter than saidmain bore, la tubular split spring lead holder sliding in the tip boreand having a lateral annular ange lon its upper end, la coil springcircumposed `on the [lead holder and compressed between said lateralange and the tip, a pusher block engaged non-rotatably land slidably inthe main barrel bore and engaged with the upper end of the lead holder,a push rod engaged slidably and rotatably in the main Ibarrel bore, saidpush rod having a reduced diameter knob yon its upper end extendingthrough said reduced diameter barrel bore and reaching ibeyond the upperend of the barrel, the upper end `of main portion of the push rod andsaid knob defining a shoulder, and laterally inwardly springapressedcatch means adapted to engage behind said shoulder in a downwardlyextended position orf the pfush rod wherein a lead engaged in the leadholder is extended `out of the tip to use position, said catch meansbeing a component of a pocket clip and catch assembly mounted on theexterior of the barrel adjacent to the upper end of the barrel, saidassembly comprising la pocket clip having a channel upper portionsecured to the barrel and a pocket clip arm extending downwardly fromsaid upper portion, said upper portion having side walls and a web, saidweb being spaced from the `barrel and having Ia longitudinal slottherein, a catch comprising a longitudinally elongated finger extendingthrough the web slot land having a lower end portion within said upperportion and an upper end portion extending above said upper portion,said finger piece having a downwardly extending fulcrum lug intermediateits ends, a depression in the barrel in which said lug is seated, and alaterally inwardly extending detent on the lower end of the lingerpiece, the sidewall of the barrel having opening means through which thedetent enters the main barrel bore and engages behind said shoulder, andspring means compressed between the web of the upper portion of the clipand the linger piece. p

5. A mechanical pencil comprising a tubular barrel having lower and.upper ends, said barrel having a main axial bore extending to saidlower lend and a reduced diameter axial boire extending from said upperend to the main bore, a tubular tip threaded into the lower end of themain bore, said tip having an axial bore smaller in `diameter than saidmain bore, a tubular split spring lead holder sliding in the tip boreand having a lateral annular ilange on its upper end, a coil springcircumposed on the lead holder and compressed between said lateralflange and the tip, `a pusher block engaged nonrotatably and slidably inthe anain barrel bore and engagcd with the upper end ot" the leadholder, a push rod engaged slidably and rotatably in the main barrelbore, said push rod having a reduced diameter knob on its upper `endextending through said reduced diameter barrel bore and reaching beyondthe upper end of the barrel, the upper end of the main portion of thepush rod and said knob denin-g a shonlder, and laterally inwardlyspring-pressed catch means adapted to engage behind said shoulder in adownwardly extended position of the push rod wherein a lead engaged inthe lead holder is extended :ont off the tip to ruse position, saidcatch means being a component of a pocket clip and catch assemblymounted ion the exterior of the barrel adjacent to the :upper end of thebarrel, said assembly comprising a pocket clip having a channel upperportion secure-d to the barrel and a pocket clip arm extendingdownwardly =irom said upper portion, said upper portion having sidewalls and a web, said web being spaced from the barrel and having alongitudinal slot therein, a catch compising a longitudinally elongatedfinger piece extending through the web slot and having a lower endportion within said upper portion and an upper end portion extendingabove said npper portion, said linger piece having a `downwardlyextending fnlorum lug intermediate its ends, a [depression in the barrelin which said lug is seated, and a late-rally inwardly extending detenton the lower end of |the linger piece, the sidewall of the banrel having`opening, means through which the detent `enters the main barrel boreand engages behind said shonlder, and spring means compressed betweenthe web of the rupper portion of the clip and the linger piece, saidspring means comprising a longitudinally elongated outwardly bowed leafspring having a lower end secured to the pocket clip arm, anintermediate portion bearing against the laterally inward side of saidclip arm, and an upper end bearing npon the laterally Koutward edge ofthe nger piece in the region of the detent.

References Cited in the tile of this patent UNITED STATES PATENTS1,583,718 Hndson May 4, 1926 2,811,945 Keller Nov. 5, 1957 FOREIGNPATENTS 964,025 France Jan. 18, 1950 286,888 Switzerland Mar. 2, 19531,125,062 France July 9, 1956

1. A MECHANICAL PENCIL COMPRISING A TUBULAR BARREL HAVING LOWER ANDUPPER ENDS, SAID BARREL HAVING A MAIN AXIAL BORE EXTENDING TO SAID LOWEREND AND A REDUCED DIAMETER AXIAL BORE EXTENDING FROM SAID UPPER END TOTHE MAIN BORE, A TUBULAR TIP THREADED INTO THE LOWER END OF THE MAINBORE, SAID TIP HAVING AN AXIAL BORE SMALLER IN DIAMETER THAN SAID MAINBORE, A TUBULAR SPLIT SPRING LEAD HOLDER SLIDING IN THE TIP BORE ANDHAVING A LATERAL ANNULAR FLANGE ON ITS UPPER END, A COIL SPRINGCIRCUMPOSED ON THE LEAD HOLDER AND COMPRESSED BETWEEN SAID LATERALFLANGE AND THE TIP, A PUSHER BLOCK ENGAGED NON-ROTATABLY AND SLIDABLY INTHE MAIN BARREL BORE AND ENGAGED WITH THE UPPER END OF THE LEAD HOLDER,A PUSH ROD ENGAGED SLIDABLY AND ROTATABLY IN THE MAIN BARREL BORE, AFEEDING AND RETRACTING SCREW SUPPORTED WITHIN SAID PUSH ROD AND THREADEDTHROUGH SAID PUSHER BLOCK, SAID PUSH ROD HAVING A REDUCED DIAMETER KNOBON ITS UPPER END EXTENDING THROUGH SAID REDUCED DIAMETER BARREL BORE ANDREACHING BEYOND THE UPPER END OF THE BARREL, THE UPPER END OF MAINPORTION OF THE PUSH ROD AND SAID KNOB DEFINING A SHOULDER, AND LATERALLYINWARDLY SPRING-PRESSED CATCH MEANS ADAPTED TO ENGAGE BEHIND SAIDSHOULDER IN A DOWNWARDLY EXTENDED POSITION OF THE PUSH ROD WHEREIN ALEAD ENGAGED IN THE LEAD HOLDER IS EXTENDED OUT OF THE TIP TO USEPOSITION.